A variety of agricultural machines include a conveyor system for transporting crop or other material from one location to another. For example, an agricultural combine typically has an unloader device that is used to unload grain from a grain tank on the combine to an external grain cart or other receptacle. A typical unloader includes a hollow passage having a crop moving device therein, such as one or more auger screws or conveyors. Movement of the auger screw or conveyor carries the material along the length of the housing until it is expelled out the end of the housing.
In some cases, an unloader may be fixed in place to a housing, but it is common for the unloader to be movable to different orientations. For example, an unloader might be movable to distribute material in different directions (e.g., to different receptacles surrounding the material supply. As another example, an unloader might be movable between a stowed position and an operative position. This latter configuration is typical on agricultural combines, which operate with the unloader in a stowed position during some of the harvesting process, and then move the unloader to the operative position extending laterally from the combine to direct crop material to a support truck or grain cart that is operated alongside the combine. This movable mounting can help protect the unloader when it is not in use, and to allow the equipment to be more maneuverable and to navigate through smaller spaces. Examples of agricultural machines having a movable unloading mechanism are shown in U.S. Pat. Nos. 7,494,409; 6,718,746; 6,638,159; 6,042,326; 5,359,838; and 5,100,281 which are incorporated herein by reference.
The inventors have determined that the state of the art still requires further advancement, particularly insofar as known unloading devices often are subject to excessive fouling by crop material, which can lead to damage or excessive service requirements.
This description of the background is provided to assist with an understanding of the following explanations of exemplary embodiments, and is not an admission that any or all of this background information is necessarily prior art.